I'm looking at trying another wheat beer and planning to add in fruit flavors. I understand the orange in most beers are made of orange rinds and a few other citrius ingredients.

However, I was thinking about using peach, and I can't use rinds or anything else but juice. My question is the juice going to affect the fermination and the flavoring of the beer? Most people I asked say that it would probably make it more sour and like a wine/mead than beer. I've done my search but haven't really found an answer. Thanks

Also, you are going to get more fermentation when you add fruit (or fruit juice), because the yeast will process the sugars.

I don't know about more sour. In my experience with other fruit flavors, I haven't found that to be a problem. I haven't made a peach beer, though.

Well the people I've asked make wine, and they said by adding in fruits or fruit extracts it would make the beer sour because it's a different type of sugar. But logically to me it seems that it would just be broken down like any other sugar and made into beer. Thanks for the input

You are right, and your friends are kind of right. Sugar is sugar, and the yeast will consume that sugar and you will get a "refermentation" (most fruit is added to a secondary) when added to the beer as the yeast will go to town on the newly-introduced sugar. I believe most sugar in fruit is fructose and sucrose, so it is highly fermentable.

Wine is "sour" (dry or crisp are better terms to use for wine-heads) due to the acid content of the grapes or other fruit used. All fruits have a varying amount of sugar and acid. See this thread, although I am not sure of the source, it lists sugar and acid content of a bunch of fruits:

Note that these numbers are not valid for fruit juice or puree as they are a function of the fresh weight, but it should give you an idea. Looks like peach is pretty low on acid compared to sugar.

Theoretically, the sugar will ferment out, leaving the acids and other compounds that contribute to the aroma and maybe flavor of the finished beer. Most fruit beer I have had that I enjoyed had a very subtle fruit character for this reason.

I have not actually made a fruit beer (yet) but am planning on experimenting with peaches, apricots, and perhaps cantelope this summer.

In theory, any wild yeast will not compete well with your beer yeast as it is in much smaller numbers and is not used to the toxic alcohol environment in the beer that has finished primary fermentation.

But to go around that, many people use an Oregon Fruit Puree instead of fresh fruit. Your LHBS should carry them or maybe might have to go to one of the online shops.

As a matter of facts, I'm currently brewing a Peach wheat; currently in secondary. I used fresh fruits, however my fruits were not very sweet... I don't know how it will turn out, so I'll keep you updated!!